TTML/changeProposal027
Links - CLOSED
- Owner: Nigel Megitt.
- Started: 27/03/14
- Closed: 20/01/15
Issues Addressed
Summary and Change details
TTML 1.0 did not define a mechanism for linking to external content.
links and embedded external content
Use cases
- A user traverses a link to display related content in a different rendering context (frame etc)
- A user performs an action related to the timed content ("vote for this candidate")
- A user selects alternate content in the same rendering context, e.g. selecting a different language from a menu
- An external image should be used to render the contained content in place of the text
- An external audio clip should be played simultaneously with the contained content
TTML2 Syntax
The <a>
element with href
and target
attributes is permitted.
The attribute actuate
may be used to define whether the link should be followed automatically, if it has the value "onLoad" or on manual request, if it has the value "onRequest". The initial value for this attribute is onRequest.
This can appear at any level and contain the children that its parents are permitted to contain.
This element may not contain any styling attributes.
Nested <a>
elements would not be permitted.
Example 1 Link
<p> <a href="http://some.org/content/more_information.html" target="below_frame"> Press your button now to view more information about this section, below. </a> </p>
Example 2 Embedded content
<p id="p241"> <a href="http://some.org/images/p241.png" target="_self" actuate="onLoad"> This text will be replaced by the referenced image. </a> </p>
Dependencies on other packages
TBD
Edits to be applied
TBD
Edits applied
Added xlink:* attributes to span and image element types in [2].
Impact
May be a different way to include embedded images than has been used in prior implementations.
References
TBD - combination of HTML <a> and xlink attributes, though not using xlink namespace.